Method of and machine for balancing the twist of elastic yarn



Nov. 317, 11936. F. D. CHITTENDEN ET AL 2,061,020

METHOD OF AND MACHINE FOR BALANCING THE TWIST OF ELASTIC YARN Filed Nov.20, 1935 WAX 7% ATTORNEY.

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Patented Nov. 17, 1936 UNITED STATES METHOIl OF AND MACHINE FOR BALANC--ING THE TWIST OF ELASTIC YARN Fayette D. Chittenden, Providence, andKenneth -.'i. Rupprecht, Harrington, R. L, assignors to United StatesRubber Products, Inc., New York, N. Y., a corporation of DelawareApplication November-'20, 1935,, Serial No. 50,666

3 Claims. (01. 117-26) This invention relates to a yarn rewindingmachine for correcting the twist of an off-balance elastic yarn, and toa method of balancing the yarn.

Elastic yarn comprising a rubber core havin a covering of textile yarnspirally wound thereupon in one direction and a second covering oftextile yarn spirally wound thereupon in an opposite direction ismanufactured in large quantities. The rubber core is held by thecovering yarns in a tensioned condition and as a result the elastic yarntends to curl and kink under the contractive force of the stretched.core unless the oppositely wound spiral covers are so, applied that theyexert a balanced actionupon the, core.

It is important that elastic yarn and particularly the finer sizesintended for use in shuttles or knitting machines be balanced whenreadyfor use so that a suspended free length thereof will hang straightand not tend to kink when free from tension, for if the yarn isunbalanced it will not work well in a shuttle or knitting machine.

In covering elastic yarn it is diflicult to always secure the desiredbalanced effect and it, has been the practice heretofore when thefinished yarn was found tobe kinky or unbalanced to correct or reclaimthe yarn by removing the .excess twist, the direction in which the yarnshould be untwisted depending upon the direction in which the yarn isoff-balance.

yarn over the, head of the spool. This operation removes one twist fromthe yarn for each revolution or coil of the yarn about the spool, butthe repeated drawing of the yarn off the end of I one spool and windingit on another to correct the twist is time consuming,

The present invention therefore contemplates a machine for correctingthe twist of off-balance elastic yam in aslngle operation instead of anumber of winding operations as heretofore, and

an important feature of the invention resides in yarn-winding mechanismincluding a spool-supporting spindle and means for rotating the ,spindleand spool at a predetermined ratio tothe speed at which the yarn ispulled fromthe spool so as to'untwist the-yarn just enough'to tomcaitsoff-balance condition.

pull roll between the spindle-operateds mews u which whi h! W 4 a isoperable to deliver the yarn to the :latterat substantially a constanttension. Other features of the invention andnovel combination ofparts'in addition to theabove will be hereinafter described inconnection with j the 5 accompanying drawing which illustrates one goodpractical form thereof. In the drawing:- Fig. 1 is a-diagrammatic sideelevation of winding mechanismconstructed in accordance with 210 thepresent invention; Y N Fig. 2 is a frontelevation of the mechanismofFig.1;. Eig. 3 is a view ofaportion of the yarn spool of Fig. 1showing the kinked elastic yarn extending therefrom, part of the yarnbeing magnified to show the inner and outer spiral covering;

and

Fig. .4 is a view similar t Fig. 3 but sh ws the rubber core as providedwith a single spiral cov- 0 ering.

In order to reclaim unbalanced elastic yarn by correcting its unbalancedcondition in accordance with the present invention the off-balance yarnis wound on a spool such as l0 so that the yarn may be pulled over thehead thereof, and

this spool is mounted upon a spindle II which is rotatably mounted insupporting means l2.

The elastic yarn I3 has beenshown in Fig. 3

as in an unbalanced kinky condition prior to having this conditioncorrected, and as here shown the elastic or rubber core l4 has spirallywound thereupon an inner cover of yarn l5 and outer cover of yarn IS.The present invention, however, may be employed to correct theunbalanced condition of other types of elastic yarn. The yarn I3 isdrawn from the spool In in an axial direction and a fixed guide ii forthe yarn is preferably provided near the upper end of the spool to guidethe yarn and cause it to balloon as 40 it leaves the spool, as shown, soas to clear the head of the spool. The yarn i3 is shown as passing fromthe guide IT to a second guide I8,positioned below ayarn-tensioning'pulley l9 about which the yarn islooped as shown. Theyarn passes from the pulley l9 through the fixed guide 20 to a guide 2|of the traversing bar 22, and then about the skein drum 23 which isdriven at the desired surface speed by the drive roll 24.

The pulley. I9 is preferably driven at a surface Qsileed several timesfaster than the surface speed "of thedrum '23 andth'e slippage of theyarn on the r-.pulley'compensates for variations in elonga- .r,tion'ofthe'elastic yarn in spooling so that the yarn is delivered to the drumunder constant tension.

The spool-supporting spindle ll may be driven by a belt 25 or otherwisebut means should be provided for controlling the speed of this spindlerelative to the speed at which the yarn is drawn off the spool H] by thewinding mechanism, so that the present mechanism may be employed to varythe amount of twist that is to be removed from the yarn.

In reclaiming 0r correcting the twist of elastic yarn in accordance withthe present invention the skeins or other packages of off-balance yarnmay be sorted into batches according to the degree af balance. They arethen spooled, that is, wound on spools such as H) and placed on thespindles II. The operator then adjusts the spindle to the proper speedfor the batch on hand. It is found that the operator after someexperience will be able to judge accurately the correct spindle speedfor any batch of yarn to be balanced. The yarn when balanced will hanglimp when tested.

As the yarn is drawn over the end of the spool ID by the rotation of thedrum 23 one twist will be removed from the yarn I3 for each revolutionof the spindle plus one turn for each wrap of yarn upon the spool, andas a result any desired number of twists can beremoved from the yarn ina single unwinding operation.

In Fig. 4 is shown a difierent type of elastic yarn comprising a rubbercore 26 having spirally wound thereupon a single covering of yarn 21.

It is apparent that if the covering 21 is wound upon an untwisted core26 the elastic yarn thus produced will be badly out of balance and willtend to kink as shown in Fig. 4. This condition, however, may be readilycorrected upon the machine of Fig. 1 by so operating this machine thatit will twist the core 26 and decrease the twist of the covering yarn 21sufficiently to produce a balanced elastic yarn having a single spiralcovering, the core being twisted in one direction and the covering inthe oppposite direction in the balanced yarn.

eration, the important feature of both the method and apparatus beingthe rotation of the package at the proper speed as the yarn is drawntherefrom.

Having thus described our invention what we claim and desire to protectby Letters Patent is:

1. The method of correcting the twist of offbalance elastic yarn, whichconsists in winding the ofi-balance yarn in a package so that the yarnmay be pulled endwise from the package as it is unwound therefrom,pulling the yarn endwise from said package, and rotating the package asthe yarn is pulled therefrom at a rate to change the twist of the yarnby a plurality of twists for each turn unwound from the package.

2. The method of correcting the twist of offbalance elasticyarn,whichconsists in winding the off-balance yarn in a package so that the yarnmay be pulled endwise from the package as it is unwound therefrom,pulling the yarn endwise from said package, and rotating said package asthe yarn is pulled therefrom at a predetermined ratio to the speed atwhich the yarn is drawn from the package.

3. The method of correcting the twist of offbalanced elastic yarn formedof a rubber core having an inner cover helically wound thereupon in onedirection and an outer cover helically wound thereupon in the oppositedirection, which consists in winding the off-balanced yarn in a packageso that the yarn may be pulled endwise from the package as it is unwoundtherefrom, pulling the yarn endwise from said package, and rotating saidpackage as the yarn is pulled therefrom at a predetermined ratio to thespeed at which the yarn is drawn from the package.

FAYETTE D. CHITTENDEN. KENNETH J. RUPPRECHT.

